Question: Express this product in scientific notation: $(6.50\times 10^{-4})\times (2.00\times 10^{5})$
Start by collecting like terms together. $= (6.50\times 2.00) \times (10^{-4}\times 10^{5})$ When multiplying exponents with the same base, add the powers together. $= 13.0 \times 10^{-4\,+\,5}$ $= 13.0 \times 10^{1}$ To write the answer correctly in scientific notation, the first number needs to be between $1$ and $10$ . In this case, we need to move the decimal one position to the left without changing the value of our answer. $ $ We can use the fact that $13.0$ is the same as $1.300 \times 10$ $ = {1.300 \times 10} \times 10^{1} $ $= 1.300\times 10^{2}$